Air purifying device



0st. 2., 1956 F, RoNDHoLz AIR PURIFYING DEVICE Filed Nov. 20, 19515mvE'HTDK. Fan?. Kon DHo z z. B

United States Patent O AIR PURIFYING DEVICE Fritz Rondliolz, Stuttgart,Germany p Application November 20, 1953, Serial No. 393,460

Claims priority, application Germany March 11, 195B 4 Claims. (Cl.183-4) The present invention relates to air purifying devices.

More particularly, the present invention relates to a device forpurifying the air in the storage space of refrigerators.

In the storage of various kinds of food stutfs together in the storagespace of mechanically driven refrigerating devices, it is well knownthat the odors of the food stuffs are transmitted from one to the other,and that, in addition to this undesirable result, the strong odor of theair usually found in enclosed cooling areas or storage spaces can becomeexceedingly troublesome. Furthermore, volatile odors from certain foodsubstances, as, for example, volatile acids evolved from cheese, mayhave an unfavorable elfect on the appearance of certain other foodsubstances, as, for example, on meats.

In order to avoid these commonly known disadvantages, some aid can befound in the use of tight containers for the food to be stored in therefrigerator, or in covering the food with odor-tight, air-tightwrapping material, as for example, aluminum or plastic sheets or foils.However, these materials are inconvenient, inadequate, or uneconomicalfor bulky food stuffs, and it has been found that they have not beenable to prevent excessive odor formation in the cooling storage space.Up to the present, there has not been achieved a means for eliminatingfrom refrigerator cooling spaces the odors which are evolved from thefood stuffs stored in the refrigerator.

It is an object, therefore, of the present invention to overcome theabove disadvantages.

It is another object of the present invention to provide a simple,economical, and effective air purifying device for eliminating odors inrefrigerator storage areas.

It is a further object of the present invention to provide a devicewhich simultaneously de-odorizes the refrigerator chamber and removeshumidity therein.

With the above objects in view, the present invention relates to arefrigerator device comprising a refrigerator housing providing anenclosed storage space adapted to receive material to be cooled therein,cooling means arranged in the refrigerator housing for cooling thestorage space and the material adapted to be stored therein, means forpurifying the air in the enclosed cold storage space by sorption ofodorous gaseous substances produced 'by the material adapted tobe storedin the enclosed storage space, and means securing the purifying means inthe refrigerator housing adjacent the cooling means therein.

Preferably, the air purifying material of the present invention consistsof granular adsorbing and absorbing air filtering compounds, thematerial being held in a container means which is provided with airpermeable walls, and which may be easily removably attached to theinterior of the refrigerator adjacent to the cooling means, i. e. theevaporator or cooling coil of the refrigeration apparatus. The airfilter material, in another embodiment of the present invention, may beheld in shaped form without the use of a container, the granular ltermaterial being held together by a binding substance.

The latter 1 lCe 2 form of the device may also be provided withattaching means for removably securing the filter material in theinterior of the refigerator, in a manner similar to the form whichincludes a container.

In research on purification of the air in refrigerator storage spaces,it has been found that the area of condensation near or at theevaporator or cooling coil is a favorable location for the collection ofodors which are evolved from the substances stored in the refrigeratorcooling space. It is in that area that the highest air humidity,strongest odor intensity and lowest vapor tension prevail, due to theinfluences of the air currents produced by the temperature conditions orby mechanically induced circulation, e. g., by a fan in the closedcooling area. These conditions are favorable for the adsorbtion ofcooling vapors in a localized area around the evaporator. For thatreason the most favorable results are assured by providing a chemical orphysical air purifier inthe region of the greatest condensation. In thisconnection, the capacity of regeneration of the air purifying materialwhich is used must be considered, since its saturation depends upon thekind and quantity of the materials stored in the cooling space.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings, inwhich:

Figure 1 is a view of a refrigerator chamber showing an embodiment of anair purifying filter of the present invention arranged therein;

Figure 2 is a perspective view of the air purifying iilter shown inFigure 1 on an enlarged scale;

Figure 3 is a sectional view of the device shown in Figure 2 taken alongthe lines 2 2;

Figure 4 is a perspective view of another embodiment of an air purifyingfilter of the present invention; and

Figure 5 is a sectional view of the embodiment shown in Figure 4.

Referring now to the drawings, and particularly to the form of thedevice shown in Figures l-3, there is shown a frame member 10 which maybe made of aluminum and which has a U-shaped cross section, the open endof the U-shaped frame being directed inwardly, as more clearly shown inFigure 3. Another frame 11 of smaller dimensions and of similar U-shapedcross-section is arranged within the outer frame 10 so that a spacing isleft between the two frames in which an inner glass mesh 12 and an outerwire mesh 13 are clamped. The frame 10 is covered on its upper portionby cover member 19. Frame 10 and cover 19 have overlapping flangeportions 101 and 191, which are clamped together by screws and bolts 14.The container 2 which is thus formed constitutes an air permeablecarrier for holding air filtering material, which is more fullydescribed below.

The container is provided with apertures at the upper ends of theclamped flanges 101 and 191, the hook elements 15 are inserted in theseapertures, the hook elements being in turn engaged by suction cupelements 16, by means of which the container 2 carrying the desired airpurifying material may be suspended in the refrigerating chamber 1, asshown in Figure 1, with the suction cup elements 16 in engagement withthe ceiling of the refrigerating chamber, so that the air purifyingcontainer 2 hangs adjacent to the evaporator 3 of the refrigerator.

Cover 19 is formed with an aperture 192, and frame 11 -is formed at itstop portion with an aperture 112, the apertures being arranged ,inregister with, one another.

Patented Oct. 2, 1956 l These apertures provide a means for filling thecontainer 2, formedbythe above described frames and mesh members, withair filtering and purifying substances, which are 'preferably .ofgranular form. Cover 19 is provided -with plate T7 for .coveringapertures 19,2 and 112 after container `2 `has been filledWith'iiltering material 18.

Both the `frames v10 and *11 and the Wire mesh )13 may be made ofaluminum or aluminum alloy, Orkpreferably of an aluminum-magnesiumalloy, inorderito avoid corrosion of .these-metallic parts.

The air 'purifyingtilter material which may be effectively `used inVtheV present invention Lfor purifying refrigerator cooling areas mayconsist of -various adsorption and absorption substancesfor removing-thegaseous odorvproducing `substances levolved by the-food stuffs'stored inthe-refrigerator. Suitable-materials Vof-this type are activated carbon,alumina, silica gel, as -well as acid-com 'bining 'basic substances,such Vas Aburnt lime, magnesia `and :ion-exchange compositions. Examplesof `the latter `compositions are Zeolites -and synthetic resin ion`exchangers. ince a single one of the lnamedcompounds lis -usually not-su'fficient ltoovercome all -of the odors, a 'mixture 4'or apluralityof -layersof lt-Wo-or-moreof the abovementionedtilteringcompounds maybeused in suit- -able'quantities The -adsorbing rair iiltermaterials whichVare described above may be regenerated for repeated use inthemannerYalready known in the art, such regeneration being ithere :results anair-disinfecting ,effectiwhich may be carried out without lossiof thecolloidalsilveror silver oxide, lsince 'the latter i materials4 may falso be regenerated as described above so as toindefinitelymaintain,thepurifying effects thereof. .In the use of .the-silver materialsmentioned,;particularly hygienic conditions inthe refrigeratorchamber-.can beachieved tosupplement and improve the odor-removingaction of the other air purifying .agents mentioned above.

vThe 'following :examples ,are f given :as `illustrative vof -mixturesof air iilteringmaterial which may be used in the present invention foreach V100 litersof refrigerator chamber space, it being'understood thattheinvention is not limited to the lspecific examples :set forth:

Example I 1D0-120 g. activated carbon, 80-100 g. of activated alumina,and 90H10() g.,of burnt lime.

Example Il lOO g. of activated carbon, 100 g. Yof activated silica gel,and 100g. ofbasic ion exchange synthetic resin.

Example III 110 g. of activated carbon,'90 g. of activated-silica gel,and 95 g. of magnesia.

Example IV l0() g. of activated carbon, 8O g. of activated alumina, and9G g. of zeolite.

In arranging the air purifying material in layers there may also beprovided hygroscopic, deliquescent chemical compounds, as for-examplecalciumchloride and magnesium chloride. These chemicals deliquesce inabsorbing'moistnre from the air, Vand* such deliquescence may impairthe-etfectiveness of theadsorbing air purifying materials. Therefore,these chemicals areprovided in the -air-lterdevice kwithirran absorbent'packing-'materiahas ltaking place in the enclosed cooling chamber.result the stored 'ifood stuffs retain their original -natural -odorAand taste, `since they are not affected by foreign 4 for example, aporous ceramic material, in order to keep them separate from "theadsorbing air filter materials.

Figures 4 and S illustrate another embodiment of the air purifyingfilter of the present invention. In these figures, there is shown aiilter device which is formed of the materials described above, butwhich, instead of being contained in an air permeable-container, isshaped into a rectangular form, the granular material of which theiilter is made being held together by any suitable binding materialsuchas glue, `synthetic resin, ;or other bindmedia.

.In thedevices `shown in Figures .4 yand 5 'bracketfmembers 22 and 23.are provided .around yfilter block 21, ,the bracket members 'havingupwardly extending 'ange portions With apertures in which hook lmembersand attaching elements similar to those described with respect to Figure2 may be inserted, so that the iilter block 21 may be hung in arefrigerator in the manner described above. Blockll thus serves as anair permeable `iilter- -ing diaphragm through which the air 'in therefrigerator may pass, uand'which'takes up by adsorptiorror absorptionthe odor-producing substances in the circulating air.

The'filter devices ofthe present invention maybeused Yin-anyrefrigerator chamber `for purifying the air therein,

the-tiltermaterial taking up by sorption, i. e., by adsorption orabsorption orlboth, the undesirable odors from the food stutfs or other-materials stored in the refrigerator, theiodors reaching-the-.lterdevice by the -air circulation As a odors :from adjacent food stuffsvwhich are removed Vby the iilter device.

|-Furthermore, the refrigerator apparatus remains Efrce .ofbdors-Whichmay detrimentally influence the `tasteof the stored materials.The'draWing-oif of 'theexcesshufmidity, which `acts as acarrying-means-for Vthe odorous substances, bytheiilter device of the persentIinvention has afurtheradvantage inthatithere is fless ice formation Aontheevaporator.orcooling coil of :therefrigerator apparatus, sov thatthe. output. of the :refrigerator .is :improved yand its :operationthereby-becomes more.economical.

:it .will vbe understood .that :cach `of .the elements described .above,or :.two vor more together, `may .also iind a useful applicationinotherttypes of airpurifyingdevices differing ffromfthe types describedabove.

While the invention ,thas :been v.illustrated .and described asiembodied'in-ahousehold refrigeratorfit is notintended :to be limitedftothe details shown, .since variousmoditications and structural changes`may :be .made vwithout-departing in rany way .from the spirit .of the:present `invention.

Without further analysis, the :foregoing will so rfully "What-isclaimedas new:and desiredto be ysecuredby Letters .'Patent 1 is 1. 1An :air:purifying device for a `refrigerator.having .an :enclosed fstorage.space -and cooling means therein,

.comprisingin combination, Vair lter material for sorption of odorousgaseous `substances produced by .material :stored in the storage .spaceof the; refrigerator, :said .air iilter materiabbeing coated with a.substance selected from the .group consisting .of colloidal :silver andcolloidal .silver oxide for disinfecting the air insaidstorage space,said lair filter .material .and `said disinfecting substance.beingadapted .to:-be regenerated'ifor. repeated.use;meansfor-:retaining theithus coated :air-:lter materialrintshaped 75zform;.fan`d attaching means-:forssecuringisaid -lterfmaterial in shapedform in the refrigerator storage space adjacent to the cooling meanstherein.

2. An air purifying device for a refrigerator having an enclosed storagespace and cooling means therein, comprising in combination, a mixture ofgranulated air filter materials for sorption of odorous gaseoussubstances produced by material stored in the storage space of therefrigerator, each component of said mixture of granulated said airfilter materials being coated with a substance selected from the groupconsisting of colloidal silver and colloidal silver oxide fordisinfecting the air in said storage space, said mixture of air filtermaterials and said disinfecting substance being adapted to beregenerated for repeated use; means for retaining the thus coatedmixture of air lter materials in shaped form; and attaching means forsecuring said mixture of lter materials in shaped form in therefrigerator storage space adjacent to the cooling means therein.

3. In an air purifying device for refrigerators, and the like, an airfilter material comprising at least one substance selected from thegroup consisting of activated carbon, silica gel and activated aluminaand being coated with a substance selected from the group consisting ofcolloidal silver and colloidal silver oxide.

4. In an air purifying device for refrigerators, and the like, an airlter comprising a mixture of granulated filter materials of at least onesubstance selected from the group consisting of activated carbon, silicagel and activated alumina and being coated with a substance selectedfrom the group consisting of colloidal silver and colloidal silveroxide.

References Cited in the file of this patent UNITED STATES PATENTS1,950,502 Madan Mar. 13, 1934 2,104,589 Hartman Ian. 4, 1938 2,117,570Philipp May 17, 1938 2,204,910 Randolph .Tune 18, 1940 2,206,705 NewmanJuly 2, 1940 2,222,882 Shames Nov. 26, 1940 2,423,702 Hart July 8, 19472,638,179 Yard May 12, 1953

3. IN AN AIR PURIFYING DEVICE FOR REFRIGERATORS, AND THE LIKE, AN AIRFILTER MATERIAL COMPRISING AT LEAST ONE SUBSTANCE SELECTED FROM THEGROUP CONSISTING OF ACTIVATED CARBON, SILICA GEL AND ACTIVATED ALUMINAAND BEING COATED WITH A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OFCOLLOIDAL SILVER AND COLLOIDAL SILVER OXIDE.